The present invention relates to an improved process for the preparation of para substituted dialkyl aromatics using H-mordenite catalysts.
The alkylation of aromatic compounds with olefins using a large number of different catalysts is old in the art. Traditional catalysts include Friedel Crafts compounds, such as AlCl.sub.3, HF, H.sub.2 SO.sub.4 and BF.sub.3. Recently, various zeolites have been reported as catalysts for the alkylation reaction.
U.S. Pat. No. 4,283,573 teaches to produce long chain alkylphenols by reacting alkanols with phenol in the presence of zeolite catalysts with preferential production of para-alkylphenols and placement of the phenolic moiety at the number two position on the alkyl chain. All examples which used mordenite as the catalyst, required the zeolite to be dealuminized until the silica/alumina weight ratio was increased to 93 from the initial ratio of 10. In all cases the amount of para-derivative was less than 70%.
U.S. Pat. No. 4,301,317 teaches to produce phenylalkanes by the reaction of benzene with alkenes in the presence of zeolite catalysts to produce primarily the 2-phenylalkane. Again, when mordenite was used as the zeolite catalyst, it was dealuminized to a silica/alumina ratio of 93. Although reaction with substituted benzene was mentioned, no examples were given and no indication of the isomer composition of the product was made.